A lateral approach allows accurate and stable total elbow replacement in dogs.

OBJECTIVE: Evaluate whether total elbow replacement (TER) through a lateral approach is accurate and stable. ANIMALS: 12 skeletally mature large-breed dog cadavers were used. METHODS: Limb alignment, elbow joint motion, and collateral ligament laxity were evaluated preoperatively. The order of surgery (left or right) and the approach (lateral or medial) were randomly selected for TER in each dog. The other approach was used in the contralateral elbow. Intraoperative technical difficulties, duration of surgery, and anatomic complications were recorded. Limb alignment, elbow joint motion, collateral ligament laxity, and prosthetic component alignment were evaluated after surgery. Data were collected from June 11 to 15, 2023. RESULTS: The duration of surgery using a lateral or medial approach did not differ (P = .499). Anatomic complications were not observed. The lateral approach resulted in 8° more elbow extension (P = .003), 1.58° less lateral collateral ligament constraint (P = .033), 2.80° less medial collateral ligament constraint (P = .002), 4.38° less frontal plane constraint (P = .004), 8° greater humeral component inclination (P = .033), and 5.6° greater radioulnar component varus (P = .001) than the medial approach. Varus of the radius, mechanical axis deviation, limb supination, elbow flexion, mediolateral humeral component and craniocaudal radioulnar component orientation did not differ among joints operated using a lateral or medial approach. In normal cadaveric elbows, a lateral approach for TER appears feasible, producing equivalent limb alignment, joint laxity, and joint motion to normal elbows and to TER placed using a medial approach. CLINICAL RELEVANCE: In dogs, TER can be performed using a lateral surgical approach.

Closed reduction and fluoroscopic-guided percutaneous pinning of femoral capital physeal or neck fractures: Thirteen fractures in 11 dogs.

OBJECTIVES: To report the short-term clinical outcome and complications in dogs that underwent surgical repair of femoral capital physeal or neck fractures via fluoroscopic-guided percutaneous pinning (FGPP). STUDY DESIGN: Retrospective case series. ANIMALS: Client owned dogs (n = 11) with femoral capital physeal or neck fractures (n = 13). METHODS: Records (July 2018-July 2021) of dogs that underwent surgery for femoral capital physeal or neck fracture repair with FGPP from two hospitals were reviewed. Data collected included signalment, age, weight, preoperative lameness severity, fracture factors (etiology, Salter-Harris classification, time from injury to surgery, radiographic displacement), surgical factors (surgery time, number/size of implants, reduction quality) and outcome (follow-up examination findings, radiographic findings, complications). RESULTS: Most fractures (11/13) occurred secondary to trauma. The median time from injury to surgery was 5.5 days. There was mild radiographic displacement preoperatively in 10/13 fractures. Satisfactory fracture healing and limb function was achieved in 10/13 femurs. Complications occurred in 5/11 cases and included intra-articular implants, implant failure/nonunion, implant migration (2), and malunion. Of these five complications, two resolved with implant removal, and a salvage procedure was recommended in the remaining cases. Of the three cases requiring salvage procedures, two originally presented with radiographic evidence of fracture chronicity. CONCLUSIONS: FGPP can be used to successfully treat femoral head and neck fractures with appropriate case selection and precise surgical technique.

Total hip replacement in dogs with contralateral pelvic limb amputation: A retrospective evaluation of 13 cases.

OBJECTIVE: To report the clinical characteristics, surgical management, and medium-term outcomes of total hip replacement (THR) performed in dogs with previous contralateral pelvic limb amputation. ANIMALS: Thirteen client-owned dogs. STUDY DESIGN: Multi-institutional retrospective clinical study. METHODS: Data recorded from medical records included signalment, indication for amputation and THR, and surgical complications. Implant positioning and complications were assessed on radiographs. Clinical outcomes were evaluated during follow-up examinations by one of the authors and through a mobility- and lifestyle-based questionnaire completed by owners. RESULTS: All 13 dogs had satisfactory clinical results at follow-up a median of 3 months (range, 2-36) after THR. No postoperative luxation was recorded. Four dogs had minor complications that did not require additional treatment. The only major complication was one failure of osseointegration of a cementless acetabular cup, and it was successfully revised. CONCLUSION: Total hip replacement resulted in satisfactory clinical results and acceptable morbidity in this population. CLINICAL SIGNIFICANCE: Total hip replacement should be considered in dogs with severe coxofemoral joint disease and contralateral pelvic limb amputation.

Interlocking Nails and Minimally Invasive Osteosynthesis.

Reviews of clinical outcomes led to the foundation of a new approach in fracture management known as biological osteosynthesis. As intramedullary rods featuring cannulations and locking devices at both extremities, interlocking nails are well suited for bridging osteosynthesis. Unique biological and mechanical benefits make them ideal for minimally invasive nail osteosynthesis and an attractive, effective alternative to plating, particularly in revisions of failed plate osteosynthesis. Thanks to a new angle-stable locking design, interlocking nailing indications have been expanded to osteosynthesis of epi-metaphyseal fractures, including those with articular involvement and angular deformities such as distal femoral varus and associated patellar luxations.

Minimally invasive percutaneous medial plate rod osteosynthesis for treatment of bicondylar humeral fractures in dogs: Surgical technique and case report.

OBJECTIVE: To describe a minimally invasive surgical technique for the treatment of comminuted humeral bicondylar (also known as T-Y) fractures in dogs and report outcome in 3 cases. STUDY DESIGN: Surgical technique description and case report. ANIMALS: Three consecutive dogs with traumatic comminuted humeral T-Y fractures. METHODS: Dogs that presented with a traumatic humeral T-Y fracture were prospectively included. The condylar component of the fractures was reduced first by using a combination of percutaneous forceps and K-wires. A transcondylar screw was applied, and epicondylar pins were preplaced medially and laterally. The metaphyseal component of the fracture was then reduced and stabilized with the pins. Finally, a bone plate was applied percutaneously along the medial humeral surface. Intraoperative fluoroscopy was used throughout surgery in all cases. Postoperative alignment in the frontal and sagittal planes was compared to the contralateral limbs. Time to clinical union, clinical outcome, and complications were recorded. RESULTS: Three dogs were included. Body weight ranged from 5.9 to 40 kg. Incomplete ossification of the humeral condyle was identified as the primary pathology leading to the fracture in 2 cases. All cases experienced uncomplicated healing with good to excellent functional recovery. CONCLUSION: The reported technique was associated with good outcomes without complications in 3 cases. CLINICAL SIGNIFICANCE: This study provides evidence that minimally invasive plate osteosynthesis represents an alternative to open reduction and internal fixation in the treatment of comminuted humeral T-Y fractures.

Minimally invasive percutaneous medial plate-rod osteosynthesis for treatment of humeral shaft fractures in dog and cats: Surgical technique and prospective evaluation.

OBJECTIVE: To describe and prospectively report outcomes associated with a novel minimally invasive percutaneous osteosynthesis (MIPO) technique for the treatment of humeral fractures in dogs and cats. STUDY DESIGN: Prospective clinical case series. ANIMALS: Eleven dogs and 4 cats with traumatic nonarticular humeral fractures. METHODS: Dogs and cats that presented with traumatic humeral fractures were enrolled in the study. After closed reduction, the fracture was stabilized by using a plate-rod combination applied via remote medial incisions. Postoperative alignment in the frontal and sagittal planes was statistically compared with the contralateral limbs. Time to clinical union and complications were also recorded. RESULTS: Eleven dogs and 4 cats were included in this study. Body weight ranged from 4.5 to 33.6 kg in dogs and from 2.2 to 3.6 kg in cats. A veterinary cuttable plate (6/11 dogs and 3/4 cats) or locking compression plate was used in a plate-rod configuration (11/11 dogs and 2/4 cats) or alone (2/4 cats). Rod-to-medullary-cavity ratio was 30%. Plate-span ratio was 5.8 (range, 2-13.5). No significant differences were found in frontal or sagittal plane alignment. Healing time in cases that completed on-time follow-up (12/15) was 36 ± 14 days (range, 20-69). No major complications were recorded. CONCLUSION: The reported technique was associated with good outcomes in a large variety of fracture configurations and animal sizes, with no complications. CLINICAL SIGNIFICANCE: This report provides evidence that MIPO is a compelling alternative to open reduction and internal fixation in the treatment of various humeral fractures.

Minimally invasive lag screw fixation of sacroiliac luxation/fracture using a dedicated novel instrument system: Apparatus and technique description.

OBJECTIVE: To describe a novel Sacroiliac Luxation Instrument System (SILIS™) and its application in minimally invasive osteosynthesis (MIO) of sacroiliac luxations/fractures (SIL/F). The SILIS was designed to provide stable SIL/F reduction and accurate sacral screw placement while reducing personnel exposure to ionizing radiation during intraoperative fluoroscopy. STUDY DESIGN: Descriptive, proof of concept cadaveric study. METHODS: A right SIL and a left SIL/F were created on a Labrador Retriever that had died of natural causes. Bilateral sacroiliac lag screw fixation was performed under fluoroscopic guidance with the SILIS, which consists of dedicated reduction and fixation instruments rigidly linked to table-bound 6-axis arms. RESULTS: Throughout surgery, the SILIS facilitated and maintained stable reduction and allowed accurate placement of a custom designed drill guide over the sacral body without the surgeon's manual holding of any reduction or fixation instruments. The surgical team was therefore able to step away from the C-arm when acquiring fluoroscopic images, thus reducing exposure to radiation. Dorsoventral and craniocaudal screw deviation from an ideal trajectory ranged from 0.9° to 3.8°. Both screws were fully located within the sacral body. CONCLUSION: The SILIS addresses limitations associated with MIO of SIL/F, including maintenance of reduction throughout surgery along with reliable and accurate sacral screw placement. Distance from the X-ray source is the most effective protection against radiation. Use of the SILIS allows the surgical team to move away from the C-arm during fluoroscopy, thereby reducing personnel exposure to dangerous direct and back-scattered ionizing radiation.

Comparison of open reduction versus minimally invasive surgical approaches on screw position in canine sacroiliac lag-screw fixation.

OBJECTIVE: To compare accuracy and consistency of sacral screw placement in canine pelves treated for sacroiliac luxation with open reduction and internal fixation (ORIF) or minimally invasive osteosynthesis (MIO) techniques. METHODS: Unilateral sacroiliac luxations created experimentally in canine cadavers were stabilized with an iliosacral lag screw applied via ORIF or MIO techniques (n = 10/group). Dorsoventral and craniocaudal screw angles were measured using computed tomography multiplanar reconstructions in transverse and dorsal planes, respectively. Ratios between pilot hole length and sacral width (PL/SW-R) were obtained. Data between groups were compared statistically (p <0.05). RESULTS: Mean screw angles (±SD) were greater in ORIF specimens in both transverse (p <0.001) and dorsal planes (p <0.004). Mean PL/SW-R was smaller (p <0.001) in the ORIF group, yet was greater than 60%. While pilot holes exited the first sacral end-plate in three of 10 ORIF specimens, the spinal canal was not violated in either group. CONCLUSIONS: This study demonstrates that MIO fixation of canine sacroiliac luxations provides more accurate and consistent sacral screw placement than ORIF. With proper techniques, iatrogenic neurological damage can be avoided with both techniques. The PL /SW-R, which relates to safe screw fixation, also demonstrates that screw penetration of at least 60% of the sacral width is achievable regardless of surgical approach. These findings, along with the limited dissection needed for accurate sacral screw placement, suggest that MIO of sacroiliac luxations is a valid alternative to ORIF.

Retrospective evaluation of concurrent intra-abdominal injuries in dogs with traumatic pelvic fractures: 83 cases (2008-2013).

OBJECTIVE: To report the occurrence of intra-abdominal injury (IA) in dogs with pelvic fractures due to blunt trauma, to evaluate for association between characterization of pelvic fractures and the presence of IA, and to evaluate for association between IA and other specific clinical conditions. DESIGN: Retrospective case series (2008-2013). SETTING: University teaching hospital. ANIMALS: Eighty-three client-owned dogs with pelvic fractures due to blunt trauma. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Pelvic injuries included pubic fractures (90.4%), ischial fractures (80.7%), sacroiliac luxations (57.8%), iliac fractures (43.4%), acetabular fractures (30.1%), and sacral fractures (13.3%). Thirty-one dogs (37%) had IA, which included hemoabdomen (27 dogs), uroabdomen (3), and septic abdomen (3); 2 dogs had 2 types of IA. Dogs with sacral fractures were significantly more likely to have IA than dogs without sacral fractures (P = 0.0162). Characterization of pelvic fractures included the direction of compression, presence of a weight-bearing bone fracture, and degree of pelvic narrowing, none of which had an association with IA (P > 0.05). Dogs were more likely to have IA if they had cardiac dysrhythmia (P = 0.0002) or hematuria (P = 0.0001), and were more likely to have a hemoabdomen if they had cardiac dysrhythmia (P = 0.0005). Dogs with hematochezia were more likely to have a septic abdomen (P = 0.0123). Dogs were more likely to receive a transfusion if they had AI (P = 0.033) or hemoabdomen specifically (P = 0.0033). Overall survival to discharge was 89%, which was significantly greater than survival in dogs with pelvic injury that also had septic abdomen (33%; P = 0.0299). CONCLUSIONS: IA is common in dogs with pelvic fractures, especially those with sacral fractures. Pelvic fracture characterization had no bearing on the presence of IA.

Comparison of three ultrasound guided approaches to the lumbar plexus in dogs: a cadaveric study.

OBJECTIVE: To assess the accuracy of contrast material injection and the dispersion of injectate following ultrasound guided injections at the level of L6 and L7, in canine cadavers. STUDY DESIGN: Prospective, randomized, experimental study. ANIMALS: Twenty nine mixed breed canine cadavers (28.9 ± 6.0 kg). METHODS: Three ultrasound-guided approaches to the lumbar plexus (LP) were compared: 1) a dorsal pre-iliac approach at the level of L6; 2) a lateral paravertebral approach at mid-L6; and 3) a lateral paravertebral approach at mid-L7. An isovolumic mixture of iodine-based contrast with new methylene blue (0.1 mL kg(-1)) was injected bilaterally in the juxta-foraminal region along the L6 or L7 nerve root. Computed tomography was performed followed by segmentation and 3D reconstruction of the lumbar spine and contrast material volumes using dedicated software. Distances between contrast material and the fifth through seventh lumbar foraminae, and length of femoral (FN) and obturator (ON) nerve staining were measured and compared between approaches (p < 0.05). RESULTS: Injectate moved cranial and caudal to the site of injection, and dispersed into an ovoid shape between the quadratus lumborum, iliopsoas and psoas minor muscles. Injections at L7 resulted in significantly closer contrast proximity to the L6 and L7 foraminae (p < 0.001). Femoral nerve staining was similar for all approaches, ON staining was more consistent after L7 injections (p < 0.001). CONCLUSION AND CLINICAL RELEVANCE: An ultrasound-guided lateral paravertebral approach to the LP proved very practical and accurate, with easy visualization of the plexus and associated nerves. To ensure that the ON is covered by injectate, an approach at the level of L7 is recommended. Further studies are necessary to determine if this correlates with clinically effective local anesthesia.

In vivo biomechanical evaluation of a novel angle-stable interlocking nail design in a canine tibial fracture model.

OBJECTIVE: To compare clinical outcome and callus biomechanical properties of a novel angle stable interlocking nail (AS-ILN) and a 6 mm bolted standard ILN (ILN6b) in a canine tibial fracture model. STUDY DESIGN: Experimental in vivo study. ANIMALS: Purpose-bred hounds (n = 11). METHODS: A 5 mm mid-diaphyseal tibial ostectomy was stabilized with an AS-ILN (n = 6) or an ILN6b (n = 5). Orthopedic examinations and radiographs were performed every other week until clinical union (18 weeks). Paired tibiae were tested in torsion until failure. Callus torsional strength and toughness were statistically compared and failure mode described. Total and cortical callus volumes were computed and statistically compared from CT slices of the original ostectomy gap. Statistical significance was set at P < .05 RESULTS: From 4 to 8 weeks, lameness was less pronounced in AS-ILN than ILN6b dogs (P < .05). Clinical union was reached in all AS-ILN dogs by 10 weeks and in 3/5 ILN6b dogs at 18 weeks. Callus mechanical properties were significantly greater in AS-ILN than ILN6b specimens by 77% (failure torque) and 166% (toughness). Failure occurred by acute spiral (control and AS-ILN) or progressive transverse fractures (ILN6b). Cortical callus volume was 111% greater in AS-ILN than ILN6b specimens (P < .05). CONCLUSIONS: Earlier functional recovery, callus strength and remodeling suggest that the AS-ILN provides a postoperative biomechanical environment more conducive to bone healing than a comparable standard ILN.

Perioperative imaging in minimally invasive osteosynthesis in small animals.

Perioperative imaging using various appropriate modalities is critical to the successful planning and performance of any orthopedic surgery. Although not an absolute prerequisite, the use of intraoperative imaging considerably facilitates the smooth and effective execution of minimally invasive osteosynthesis (MIO). However, the risk of overexposure to radiation is real, particularly when considering its insidious effect over time. Therefore, the primary concern of the surgeon must be safety of the surgical team. This article outlines basic, simple steps that will be effective in reducing radiation exposure, which in turn will make MIO a safe alternative to open reduction and internal fixation.

Interlocking nails and minimally invasive osteosynthesis.

Interlocking nailing of long bone fractures has long been considered the gold standard osteosynthesis technique in people. Thanks to improvements in the locking mechanism design and nail profile, a recently developed veterinary angle stable nail has become the first true intramedullary fixator providing accurate and consistent repair stability while allowing semirigid fixation. As a result, indications for interlocking nailing have expanded to include treatment of periarticular fractures, corrections of angular deformities and revisions of failed plate osteosyntheses. Perfectly suited for minimally invasive osteosynthesis, interlocking nailing is an attractive and effective alternative to bone plating and plate-rod fixation technique.

Prospective evaluation of minimally invasive plate osteosynthesis in 36 nonarticular tibial fractures in dogs and cats.

OBJECTIVE: To evaluate the clinical outcome of minimally invasive plate osteosynthesis (MIPO) for nonarticular tibial fractures stabilized using bone plates with or without an intramedullary rod (IMR). STUDY DESIGN: Prospective study. ANIMALS: Dogs (n=28) and 8 cats. METHODS: After closed reduction, fracture fixation was achieved using an epiperiosteal plate inserted percutaneously through epiphyseal small incisions. In some fractures, an IMR was inserted via medial parapatellar arthrotomy. Radiographs were recommended every 3 weeks until clinical union. Postoperative tibial length and alignment were compared with contralateral measurements (P<.05). Time to clinical union and complications were recorded. RESULTS: An IMR was used in 30.5% of the cases. Repaired tibiae were 1% shorter than contralateral tibiae (P<.05). Frontal and sagittal alignment were similar between repaired and contralateral tibiae (P>.05). Six dogs were lost for follow-up; owners indicated normal function. In 30 cases for which bone healing was documented, mean±SD healing time was 45±20.8 days; however, when considering the 23 cases, which completed preestablished scheduled follow-ups, healing time was 36±11.6 days. Minor complications occurred in 4 cases (11%). One major complication (3%) consisting of a plate fracture was successfully revised using MIPO with a larger plate. CONCLUSIONS: Consistent restoration of alignment was accomplished using MIPO techniques. Furthermore, MIPO appeared to yield faster healing times and lower complication rates than those reported with conventional plate osteosynthesis.

Hiatal hernia in the dog: a clinical report of four Chinese shar peis.

Four Chinese shar pei littermate puppies were presented for vomiting, regurgitation, hypersalivation, and poor growth. Diagnosis of hiatal hernia was made for each of the four dogs based on survey radiographs and barium esophagram studies. All dogs initially underwent medical therapy, to which only one dog responded. All dogs underwent surgical treatment, which included manual hernia reduction followed by phrenoplasty, esophagopexy, and left incisional gastropexy, 5 to 40 days following initiation of medical therapy. The three surgical techniques described eliminated the need to enter the pleural cavity and offered excellent long-term results with no recurrence of clinical signs following surgery.